package Leetcode;

public class ListNode {
    int val;
    ListNode next;
    ListNode() {

    }
    ListNode(int val) {
        this.val = val;
    }
    ListNode(int val, ListNode next) {
        this.val = val;
        this.next = next;
    }

    @Override
    public String toString() {
        return "ListNode{" +
                "val=" + val +
                ", next=" + next +
                '}';
    }
}
class Solution {
    public ListNode mergeTwoLists(ListNode list1, ListNode list2) {

        if (list1 == null){
            return list2;
        } else if (list2 == null){
            return list1;
        } else if (list1.val < list2.val){
            list1.next = mergeTwoLists(list1.next,list2);
            return list1;
        } else {
            list2.next = mergeTwoLists(list2.next,list1);
            return list2;
        }

    }

    public static void main(String[] args) {

        Solution st = new Solution();

        ListNode list1 = new ListNode(1,new ListNode(2,new ListNode(4)));
        ListNode list2 = new ListNode(1,new ListNode(3,new ListNode(4)));

        System.out.println(st.mergeTwoLists(list1, list2));


    }
}
